diff --git a/scripts/runqemu b/scripts/runqemu
index 1277e82dd9..84ece4d7e4 100755
--- a/scripts/runqemu
+++ b/scripts/runqemu
@@ -62,7 +62,7 @@ MACHINE=${MACHINE:=""}
 KERNEL=${KERNEL:=""}
 ROOTFS=${ROOTFS:=""}
 VM=${VM:=""}
-FSTYPE=""
+FSTYPE=${FSTYPE:=""}
 LAZY_ROOTFS=""
 SCRIPT_QEMU_OPT=""
 SCRIPT_QEMU_EXTRA_OPT=""